1 /* Definitions for values of C expressions, for GDB.
2 Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
3 1996, 1997, 1998, 1999, 2000, 2001
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
23 #if !defined (VALUE_H)
27 * The structure which defines the type of a value. It should never
28 * be possible for a program lval value to survive over a call to the inferior
29 * (ie to be put into the history list or an internal variable).
34 /* Type of value; either not an lval, or one of the various
35 different possible kinds of lval. */
37 /* Is it modifiable? Only relevant if lval != not_lval. */
39 /* Location of value (if lval). */
42 /* If lval == lval_memory, this is the address in the inferior.
43 If lval == lval_register, this is the byte offset into the
44 registers structure. */
46 /* Pointer to internal variable. */
47 struct internalvar
*internalvar
;
48 /* Number of register. Only used with
49 lval_reg_frame_relative. */
53 /* Describes offset of a value within lval of a structure in bytes.
54 If lval == lval_memory, this is an offset to the address.
55 If lval == lval_register, this is a further offset from
56 location.address within the registers structure.
57 Note also the member embedded_offset below. */
59 /* Only used for bitfields; number of bits contained in them. */
61 /* Only used for bitfields; position of start of field.
62 For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB.
63 For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */
65 /* Frame value is relative to. In practice, this address is only
66 used if the value is stored in several registers in other than
67 the current frame, and these registers have not all been saved
68 at the same place in memory. This will be described in the
69 lval enum above as "lval_reg_frame_relative". */
72 /* Type of the value. */
75 /* If a value represents a C++ object, then the `type' field gives
76 the object's compile-time type. If the object actually belongs
77 to some class derived from `type', perhaps with other base
78 classes and additional members, then `type' is just a subobject
79 of the real thing, and the full object is probably larger than
82 If `type' is a dynamic class (i.e. one with a vtable), then GDB
83 can actually determine the object's run-time type by looking at
84 the run-time type information in the vtable. When this
85 information is available, we may elect to read in the entire
86 object, for several reasons:
88 - When printing the value, the user would probably rather see
89 the full object, not just the limited portion apparent from
90 the compile-time type.
92 - If `type' has virtual base classes, then even printing
93 `type' alone may require reaching outside the `type'
94 portion of the object to wherever the virtual base class
97 When we store the entire object, `enclosing_type' is the
98 run-time type --- the complete object --- and `embedded_offset'
99 is the offset of `type' within that larger type, in bytes. The
100 VALUE_CONTENTS macro takes `embedded_offset' into account, so
101 most GDB code continues to see the `type' portion of the value,
102 just as the inferior would.
104 If `type' is a pointer to an object, then `enclosing_type' is a
105 pointer to the object's run-time type, and `pointed_to_offset'
106 is the offset in bytes from the full object to the pointed-to
107 object --- that is, the value `embedded_offset' would have if
108 we followed the pointer and fetched the complete object. (I
109 don't really see the point. Why not just determine the
110 run-time type when you indirect, and avoid the special case?
111 The contents don't matter until you indirect anyway.)
113 If we're not doing anything fancy, `enclosing_type' is equal to
114 `type', and `embedded_offset' is zero, so everything works
116 struct type
*enclosing_type
;
118 int pointed_to_offset
;
120 /* Values are stored in a chain, so that they can be deleted
121 easily over calls to the inferior. Values assigned to internal
122 variables or put into the value history are taken off this
126 /* ??? When is this used? */
134 /* Register number if the value is from a register. Is not kept
135 if you take a field of a structure that is stored in a
136 register. Shouldn't it be? */
138 /* If zero, contents of this value are in the contents field.
139 If nonzero, contents are in inferior memory at address
140 in the location.address field plus the offset field
141 (and the lval field should be lval_memory).
143 WARNING: This field is used by the code which handles
144 watchpoints (see breakpoint.c) to decide whether a particular
145 value can be watched by hardware watchpoints. If the lazy flag
146 is set for some member of a value chain, it is assumed that
147 this member of the chain doesn't need to be watched as part of
148 watching the value itself. This is how GDB avoids watching the
149 entire struct or array when the user wants to watch a single
150 struct member or array element. If you ever change the way
151 lazy flag is set and reset, be sure to consider this use as
154 /* If nonzero, this is the value of a variable which does not
155 actually exist in the program. */
157 /* The BFD section associated with this value. */
158 asection
*bfd_section
;
159 /* Actual contents of the value. For use of this value; setting
160 it uses the stuff above. Not valid if lazy is nonzero.
161 Target byte-order. We force it to be aligned properly for any
162 possible value. Note that a value therefore extends beyond
163 what is declared here. */
167 double force_double_align
;
168 LONGEST force_longlong_align
;
172 /* Do not add any new members here -- contents above will trash them */
175 typedef struct value
*value_ptr
;
177 #define VALUE_TYPE(val) (val)->type
178 #define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type
179 #define VALUE_LAZY(val) (val)->lazy
180 /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of
181 the gdb buffer used to hold a copy of the contents of the lval.
182 VALUE_CONTENTS is used when the contents of the buffer are needed --
183 it uses value_fetch_lazy() to load the buffer from the process being
184 debugged if it hasn't already been loaded. VALUE_CONTENTS_RAW is
185 used when data is being stored into the buffer, or when it is
186 certain that the contents of the buffer are valid.
187 Note: The contents pointer is adjusted by the offset required to
188 get to the real subobject, if the value happens to represent
189 something embedded in a larger run-time object. */
191 #define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents + (val)->embedded_offset)
192 #define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\
193 VALUE_CONTENTS_RAW(val))
195 /* The ALL variants of the above two macros do not adjust the returned
196 pointer by the embedded_offset value. */
198 #define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents)
199 #define VALUE_CONTENTS_ALL(val) ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)),\
200 VALUE_CONTENTS_ALL_RAW(val))
203 extern int value_fetch_lazy (value_ptr val
);
205 #define VALUE_LVAL(val) (val)->lval
206 #define VALUE_ADDRESS(val) (val)->location.address
207 #define VALUE_INTERNALVAR(val) (val)->location.internalvar
208 #define VALUE_FRAME_REGNUM(val) ((val)->location.regnum)
209 #define VALUE_FRAME(val) ((val)->frame_addr)
210 #define VALUE_OFFSET(val) (val)->offset
211 #define VALUE_BITSIZE(val) (val)->bitsize
212 #define VALUE_BITPOS(val) (val)->bitpos
213 #define VALUE_NEXT(val) (val)->next
214 #define VALUE_REGNO(val) (val)->regno
215 #define VALUE_OPTIMIZED_OUT(val) ((val)->optimized_out)
216 #define VALUE_EMBEDDED_OFFSET(val) ((val)->embedded_offset)
217 #define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset)
218 #define VALUE_BFD_SECTION(val) ((val)->bfd_section)
220 /* Convert a REF to the object referenced. */
222 #define COERCE_REF(arg) \
223 do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\
224 if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \
225 arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \
226 unpack_pointer (VALUE_TYPE (arg), \
227 VALUE_CONTENTS (arg)), \
228 VALUE_BFD_SECTION (arg)); \
231 /* If ARG is an array, convert it to a pointer.
232 If ARG is an enum, convert it to an integer.
233 If ARG is a function, convert it to a function pointer.
235 References are dereferenced. */
237 #define COERCE_ARRAY(arg) \
238 do { COERCE_REF(arg); \
239 if (current_language->c_style_arrays \
240 && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \
241 arg = value_coerce_array (arg); \
242 if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \
243 arg = value_coerce_function (arg); \
246 #define COERCE_NUMBER(arg) \
247 do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0)
249 #define COERCE_VARYING_ARRAY(arg, real_arg_type) \
250 { if (chill_varying_type (real_arg_type)) \
251 arg = varying_to_slice (arg), real_arg_type = VALUE_TYPE (arg); }
253 /* If ARG is an enum, convert it to an integer. */
255 #define COERCE_ENUM(arg) { \
256 if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \
257 arg = value_cast (builtin_type_unsigned_int, arg); \
260 /* Internal variables (variables for convenience of use of debugger)
261 are recorded as a chain of these structures. */
265 struct internalvar
*next
;
270 /* Pointer to member function. Depends on compiler implementation. */
272 #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000)
273 #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET))
274 #define METHOD_PTR_TO_VOFFSET(ADDR) (~0x80000000 & (ADDR))
278 #include "gdbtypes.h"
279 #include "expression.h"
284 extern void print_address_demangle (CORE_ADDR
, struct ui_file
*, int);
286 extern LONGEST
value_as_long (value_ptr val
);
288 extern DOUBLEST
value_as_double (value_ptr val
);
290 extern CORE_ADDR
value_as_pointer (value_ptr val
);
292 extern LONGEST
unpack_long (struct type
*type
, char *valaddr
);
294 extern DOUBLEST
unpack_double (struct type
*type
, char *valaddr
, int *invp
);
296 extern CORE_ADDR
unpack_pointer (struct type
*type
, char *valaddr
);
298 extern LONGEST
unpack_field_as_long (struct type
*type
, char *valaddr
,
301 extern value_ptr
value_from_longest (struct type
*type
, LONGEST num
);
303 extern value_ptr
value_from_pointer (struct type
*type
, CORE_ADDR addr
);
305 extern value_ptr
value_from_double (struct type
*type
, DOUBLEST num
);
307 extern value_ptr
value_from_string (char *string
);
309 extern value_ptr
value_at (struct type
*type
, CORE_ADDR addr
,
312 extern value_ptr
value_at_lazy (struct type
*type
, CORE_ADDR addr
,
315 extern value_ptr
value_from_register (struct type
*type
, int regnum
,
316 struct frame_info
*frame
);
318 extern value_ptr
value_of_variable (struct symbol
*var
, struct block
*b
);
320 extern value_ptr
value_of_register (int regnum
);
322 extern int symbol_read_needs_frame (struct symbol
*);
324 extern value_ptr
read_var_value (struct symbol
*var
,
325 struct frame_info
*frame
);
327 extern value_ptr
locate_var_value (struct symbol
*var
,
328 struct frame_info
*frame
);
330 extern value_ptr
allocate_value (struct type
*type
);
332 extern value_ptr
allocate_repeat_value (struct type
*type
, int count
);
334 extern value_ptr
value_change_enclosing_type (value_ptr val
, struct type
*new_type
);
336 extern value_ptr
value_mark (void);
338 extern void value_free_to_mark (value_ptr mark
);
340 extern value_ptr
value_string (char *ptr
, int len
);
341 extern value_ptr
value_bitstring (char *ptr
, int len
);
343 extern value_ptr
value_array (int lowbound
, int highbound
,
344 value_ptr
* elemvec
);
346 extern value_ptr
value_concat (value_ptr arg1
, value_ptr arg2
);
348 extern value_ptr
value_binop (value_ptr arg1
, value_ptr arg2
,
351 extern value_ptr
value_add (value_ptr arg1
, value_ptr arg2
);
353 extern value_ptr
value_sub (value_ptr arg1
, value_ptr arg2
);
355 extern value_ptr
value_coerce_array (value_ptr arg1
);
357 extern value_ptr
value_coerce_function (value_ptr arg1
);
359 extern value_ptr
value_ind (value_ptr arg1
);
361 extern value_ptr
value_addr (value_ptr arg1
);
363 extern value_ptr
value_assign (value_ptr toval
, value_ptr fromval
);
365 extern value_ptr
value_neg (value_ptr arg1
);
367 extern value_ptr
value_complement (value_ptr arg1
);
369 extern value_ptr
value_struct_elt (value_ptr
* argp
, value_ptr
* args
,
371 int *static_memfuncp
, char *err
);
373 extern value_ptr
value_struct_elt_for_reference (struct type
*domain
,
375 struct type
*curtype
,
377 struct type
*intype
);
379 extern value_ptr
value_static_field (struct type
*type
, int fieldno
);
381 extern struct fn_field
*value_find_oload_method_list (value_ptr
*, char *,
383 struct type
**, int *);
385 extern int find_overload_match (struct type
**arg_types
, int nargs
,
386 char *name
, int method
, int lax
,
387 value_ptr obj
, struct symbol
*fsym
,
388 value_ptr
* valp
, struct symbol
**symp
,
391 extern value_ptr
value_field (value_ptr arg1
, int fieldno
);
393 extern value_ptr
value_primitive_field (value_ptr arg1
, int offset
,
394 int fieldno
, struct type
*arg_type
);
397 extern struct type
*value_rtti_target_type (value_ptr
, int *, int *, int *);
399 extern value_ptr
value_full_object (value_ptr
, struct type
*, int, int, int);
401 extern value_ptr
value_cast (struct type
*type
, value_ptr arg2
);
403 extern value_ptr
value_zero (struct type
*type
, enum lval_type lv
);
405 extern value_ptr
value_repeat (value_ptr arg1
, int count
);
407 extern value_ptr
value_subscript (value_ptr array
, value_ptr idx
);
409 extern value_ptr
value_from_vtable_info (value_ptr arg
, struct type
*type
);
411 extern value_ptr
value_being_returned (struct type
*valtype
,
412 char *retbuf
, int struct_return
);
414 extern value_ptr
value_in (value_ptr element
, value_ptr set
);
416 extern int value_bit_index (struct type
*type
, char *addr
, int index
);
418 extern int using_struct_return (value_ptr function
, CORE_ADDR funcaddr
,
419 struct type
*value_type
, int gcc_p
);
421 extern void set_return_value (value_ptr val
);
423 extern value_ptr
evaluate_expression (struct expression
*exp
);
425 extern value_ptr
evaluate_type (struct expression
*exp
);
427 extern value_ptr
evaluate_subexp_with_coercion (struct expression
*,
430 extern value_ptr
parse_and_eval (char *exp
);
432 extern value_ptr
parse_to_comma_and_eval (char **expp
);
434 extern struct type
*parse_and_eval_type (char *p
, int length
);
436 extern CORE_ADDR
parse_and_eval_address (char *exp
);
438 extern CORE_ADDR
parse_and_eval_address_1 (char **expptr
);
440 extern LONGEST
parse_and_eval_long (char *exp
);
442 extern value_ptr
access_value_history (int num
);
444 extern value_ptr
value_of_internalvar (struct internalvar
*var
);
446 extern void set_internalvar (struct internalvar
*var
, value_ptr val
);
448 extern void set_internalvar_component (struct internalvar
*var
,
450 int bitpos
, int bitsize
,
453 extern struct internalvar
*lookup_internalvar (char *name
);
455 extern int value_equal (value_ptr arg1
, value_ptr arg2
);
457 extern int value_less (value_ptr arg1
, value_ptr arg2
);
459 extern int value_logical_not (value_ptr arg1
);
463 extern value_ptr
value_of_this (int complain
);
465 extern value_ptr
value_x_binop (value_ptr arg1
, value_ptr arg2
,
467 enum exp_opcode otherop
, enum noside noside
);
469 extern value_ptr
value_x_unop (value_ptr arg1
, enum exp_opcode op
,
472 extern value_ptr
value_fn_field (value_ptr
* arg1p
, struct fn_field
*f
,
473 int j
, struct type
*type
, int offset
);
475 extern int binop_user_defined_p (enum exp_opcode op
,
476 value_ptr arg1
, value_ptr arg2
);
478 extern int unop_user_defined_p (enum exp_opcode op
, value_ptr arg1
);
480 extern int destructor_name_p (const char *name
, const struct type
*type
);
482 #define value_free(val) xfree (val)
484 extern void free_all_values (void);
486 extern void release_value (value_ptr val
);
488 extern int record_latest_value (value_ptr val
);
491 modify_field (char *addr
, LONGEST fieldval
, int bitpos
, int bitsize
);
493 extern void type_print (struct type
* type
, char *varstring
,
494 struct ui_file
* stream
, int show
);
496 extern char *baseclass_addr (struct type
*type
, int index
,
497 char *valaddr
, value_ptr
* valuep
, int *errp
);
499 extern void print_longest (struct ui_file
* stream
, int format
,
500 int use_local
, LONGEST val
);
502 extern void print_floating (char *valaddr
, struct type
* type
,
503 struct ui_file
* stream
);
505 extern int value_print (value_ptr val
, struct ui_file
*stream
, int format
,
506 enum val_prettyprint pretty
);
508 extern void value_print_array_elements (value_ptr val
,
509 struct ui_file
*stream
,
511 enum val_prettyprint pretty
);
513 extern value_ptr
value_release_to_mark (value_ptr mark
);
515 extern int val_print (struct type
* type
, char *valaddr
,
516 int embedded_offset
, CORE_ADDR address
,
517 struct ui_file
* stream
, int format
,
518 int deref_ref
, int recurse
,
519 enum val_prettyprint pretty
);
521 extern int val_print_string (CORE_ADDR addr
, int len
, int width
, struct ui_file
*stream
);
523 extern void print_variable_value (struct symbol
* var
,
524 struct frame_info
* frame
,
525 struct ui_file
*stream
);
527 extern int check_field (value_ptr
, const char *);
529 extern void typedef_print (struct type
* type
, struct symbol
* news
,
530 struct ui_file
* stream
);
532 extern char *internalvar_name (struct internalvar
*var
);
534 extern void clear_value_history (void);
536 extern void clear_internalvars (void);
540 extern value_ptr
value_copy (value_ptr
);
542 extern int baseclass_offset (struct type
*, int, char *, CORE_ADDR
);
546 extern value_ptr
varying_to_slice (value_ptr
);
548 extern value_ptr
value_slice (value_ptr
, int, int);
550 extern value_ptr
call_function_by_hand (value_ptr
, int, value_ptr
*);
552 extern int default_coerce_float_to_double (struct type
*, struct type
*);
554 extern int standard_coerce_float_to_double (struct type
*, struct type
*);
556 extern value_ptr
value_literal_complex (value_ptr
, value_ptr
, struct type
*);
558 extern void find_rt_vbase_offset (struct type
*, struct type
*, char *, int,
561 extern value_ptr
find_function_in_inferior (char *);
563 extern value_ptr
value_allocate_space_in_inferior (int);
565 extern CORE_ADDR
default_push_arguments (int nargs
, value_ptr
* args
,
568 CORE_ADDR struct_addr
);
570 #endif /* !defined (VALUE_H) */